Is there an incomplete normed space which is Asplund?

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Can there exist an incomplete normed space which is Asplund?

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The property of being an Asplund space is normally defined for Banach spaces only. If you try to apply the same definition without requiring completeness, the question arises: which of many definitions to use? These are known to be equivalent for Banach spaces.

Most of the definitions refer to the dual space (i.e., $X$ is Asplund iff $X^*$ has the Radon–Nikodým property; or if every separable subspace of $X$ has separable dual). If $X$ is a dense subspace of a Banach space $Y$ (with the same norm), then $X^*=Y^*$, and similarly for subspaces. So, $Y$ being Asplund implies $X$ being Asplund, by these definitions.

In particular, the space of sequences that are eventually zero, equipped with the $\ell^2$ norm, would be an incomplete Asplund space according to the above.